Users can browse for video content as well as login to their
personal YouTube accounts to view and save their favorite videos.

In addition, Apple announced that its upcoming iPhone
will also feature YouTube support when it launches on June 29. iPhone users
will be able to browse YouTube content through EDGE networks or through the
built-in WiFi connection. The iPhone will also be able to take advantage of
H.264-encoded videos -- over 10,000 videos encoded in H.264 will be available
for viewing on June 29.

"iPhone delivers the best YouTube mobile experience by
far," said Apple CEO Steve Jobs. "Now users can enjoy YouTube
wherever they are -- on their iPhone, on their Mac or on a widescreen TV in
their living room with Apple TV."

Well, the YouTube web site's got ads obviously, and I think you can bet that as the mix of people viewing content through devices like this increases, they will insert ads before and after your chosen video. It's probably not really a question of "if," but "when."